Pipe wrench



SePt- 6 1927' H. w. FLETCHER PIPE WRENCH F i1ed June 27, 1922 @H501 may,

Patented Sept. 6, 1927.

UNITED STATES 1,641,260 PATENT oFFlcE.

HAROLD W. FLETCHER, OF HOUSTON, TEXAS, ASSIGNOR TO I-IIIGHESTOOL COMPAIVY,l 0F HOUSTON, TEXAS, A CORPORATION OF TEXAS.

PIPE WRENCH.

Application led June 27, 192.2. Serial No. 571,284.

This invention relates to improvements in pipe wrenches and more especially to that type of pipe wrench used for screwing and unscrewing sections of casing, drill stem, or tubing employed in'well drilling. j One object of the present invention is to provide ka Wrench of the heavy oil well type which will have a wide range of adjustability and which can be applied to a pipe and locked thereon with a minimum loss of time and labor.

Another object of my invention isto provide a pipe wrench which will have a firm gripping action upon the pipe to be screwed or unscrewed without also tending to muti- 4late or crush the pipe.

Referring to the drawing forming a part of this specification and in which like numerals of reference are applied to like parts in each of the views, Fig. 1 is a top plan view of a wrench embodying my invention, showing the pipe in transverse section. Fig. 2 is a similar view showing the jaws in slightly dierent relative positions. Fig. 3 is a diagrammatic view of the head and jaws illustrating the flexibility of my construct-ion.

In a construction of my improved type of wrench I employ a handle 8 having, at its rearward end, an eye 9 for attachment to a cable when desired. The forward yend of the handle is formed into a head 10 having a laterally projecting arm 11 thereon, said arm-being provided with an opening to receive'a pin 12 forming a pivotal attachment for a segmental jaw 13.' vSaid jaw 13 is pivoted at its other end, by means of a pin 14, to a second segmental jaw 15, the forward end of which is hooked at 16 to provide a transverse groove or recess 17 'to receive a latching yoke or link 18. The form of the yoke`18 is somewhat U-shaped, the legs of which are pivoted to the head of the wrench at 19 and said yoke is adapted toswing on the axis of the pin 19 and engage the hooked end of the jaw 15. A handle 20 at the outer end of said latch facilitates its operation. A similar handle 21 on the outer face of the jaw 15 assists the operator in handling said. jaw.

The inner faces `of each of the` jaws are formed each with a transverse groove therein to receive a triangular shaped tooth 22. As shown in the drawings, I contemplate using but one tooth on each of the jaws 13 and 15. `These teeth will be .placed in positions diametrically opposite to each other when the Wrench is applied to the particular slze of the pipe to which it is best adapted. They will be made of a special hardened steel, yand when the jaws are drawn together against the pipe the full force of the clamping action of the jaws will be exerted at the two approximately opfposite points where. the teeth contact with the pipe; thus the teeth will be forced to grip firmly upon the pipe and prevent the rotation of vthe pipe'within the jaws.

In operation, this wrench is very flexible. It will accommodate itself'to varying sizes of pipe in a manner whichv is unusual'with this heavy type of tool. The pivot 19 of' the latching yoke is approximately in the line of the central axis of the handle as shown in Fig. 3. The pivotal point l12 of the jaw 13 is offset materially t'o one side of this axis; thus, when the handlel is moved to the right as shown in Fig. 3, supposing the jaw 13 to remain stationary, the .for-

ward end 16erl the jaw 15 will be drawn inwardly toward the jaw 13 to clamp the teeth against the pipe. The handle S may be considered as fulcrumed at. the pivotal point 12 on the jaw 13. The handle here forms the lever and the load will be exerted through the latching yoke and jaw '15 secured to the lever at the pivotal point 19.

It will then be obvious that the swinging of the handle will exert a greater force.l upon the jaw 15 when the handle is in the position shown in full lines in Fig. 3, than when said handle has moved around into the position shown by the dotted line A. For, when the handle is in the position as shown in full lines, .the force will be exerted upon the load along the line B and when the handle is in the-position shown by line A the load will exert a pull4 along the line C. It will be seen that the angle formed between the lines E and C will be a right angle and that the resultant load exerts a pull at a point farthest from the fulcrum when this angle is a right angle than when the -angle is an obtuse angle as is shown when the handle is in the first yposition shown in Fig. 3. When the-handle is swung still farther into the position shown at D, the resultant load,

Aeo

shown by line F, will move closer to the fulcrum and the power-exerted upon the jaw will be greater, the force being considered constant. t

' By bending the forward end of the head f the handle so as-to offset the pivotal point- 12 it will be observed that a greater iiexibility of the wrench will be obtained. When the handle is in the position shown in full y lines in Fig. 3, it will be adapted to receive t a large pipe as shownin Fig. 1, but when a v smaller plpeis to be gripped by this'wrench,

the handle, will be swung farther around into the A or D position as far as necessar to properly clamp the size of pipe desire vThis position of the wrench is shown in Fig. 2. This adjustability of jaws for different sizes of pipe could not be obtained except with this particular formation of the head of the wrench and the particular means b which the jaws and yokevare pivoted twill also be seen from Fig. 3 that the force exerted upon theA pipe will not increase greatly as the jaws are clamped against the pipe, for the ltendency will be to decrease the clamping action slightly as the handle is swung relatively to the jaws'. It will be decreased' until the handle reaches the position y tect lzylLetters Patent isz as shown b line A and will then lncrease somewhat ue to the fact that the load is, 1n, eect, nearer the fulcrum. There will,

l however, yb e no extremely heavy 'clamping action tendin to crush or mutilate the plpe as the handle `isswung in the direction necessarv to unscrew thejoint. he forming of but two teeth makes it possible to exert the full force of the clamplng action atthe twoopposed oints; thus, tending to cause the teeth to ite into the pipe and prevent it from slipping. rIhis is an especially 'efficient 'typeV of gripping means. It is now believed that the advantages of this type of construction will be rully ,understood by those vskilled in the art Iwithout further description. 4

What I claim asnew and desire to proa pipe wrench, a handle, a head thereon havingv two' openings therein, the' vforward one oilr'set from the lcentral axis of the handle the other openingv being located upon saidvaxis, a segmental jaw pivoted inV said forward opening, a second jaw pivoted,

to said iirst named jaw, a'` latching member pivoted in the rear opening and engaging said second .'aw wherebysaid jaws are lven a wide iiexi lity of movement towar` and from each yother as said handle is swung laterally.

2. Ina pipe wrench, a handle, a` segmenbeing .adapted to be released by' movement of said handle lin one direction..v

3.' In a pipe wrench, a handle, a forward head bent laterally and provided with an opening constituting a fu crum, a jaw pivoted in said opening, a second jaw pivoted to the first jaw, a latchin oke pivoted to said head centrally of said 4lieadand to the,

rear of said fulcrum, said latch engagingwith said second jaw to draw it toward said firstnamed jaw and acting to give the jaws a wide range of adjustability as said handle `is moved in one direction.

4. In a pi e wrench, a handle, a ing a latera ly curved forward end, a pipe l,engaging 4jaw pivotally secured on said curved end, a second jaw ivotally connected to the first said jaw, a l ooked end therehead havon, and a yoke pivoted centrally of said head i to the rear of said curved end and adapted to engage over the hooked end of said second jaw. l

In testimony whereof, I hereunto my signature, this the 24th day of June, A. D.

' HAROLD. W. FLETCHER. 

